Moderate Interstitial Fibrosis Research Articles

Gonadal alterations in male eelpout ( Zoarces viviparus) exposed to ethinylestradiol and trenbolone separately or in combination

To evaluate the interaction between 17β-trenbolone (TB) and 17α-ethinylestradiol (EE2) in relevant environmental concentrations, male eelpout Zoarces viviparus were exposed in a flow-through seawater-system for 21 days to 5 ng l −1 EE2, 5 ng l −1 or 20 ng l −1 TB or to combinations of both compounds. The effects on hepatosomatic index (HSI), gonadosomatic index (GSI) and gonadal histology were studied. No significant effects on HSI were observed in any treatment; in contrast, decreased GSI was observed in males exposed to EE2 alone or in combination with TB compared to controls ( p < 0.05). The histology revealed that the males were in the beginning of spermatogenesis. Males from the control group and some from the TB groups showed tubules with cysts containing spermatogonia, spermatocytes and spermatids; however, some testes of males exposed to TB showed slight to moderate interstitial fibrosis. Nevertheless, the most severely affected were males exposed to EE2 showing marked interstitial fibrosis, necrosis of germinal cells and reduced number of spermatocytes and spermatogonia in the cyst. Likewise, increased tubule number and proportionally decreased tubule diameter were observed in the testis of all EE2 exposed groups ( p < 0.05). Finally, a similar tubule number was observed in males exposed to EE2 + 20 ng l −1 TB compared to control ( p > 0.05). This study shows that EE2 dramatically disrupts the spermatogenesis and low doses of 17β-trenbolone are unable to effectively counteract the morphological effects of EE2.

Single versus dual renal transplantation from donors with significant arteriosclerosis on pre‐implant biopsy

Transplantation of kidneys from donor with arteriosclerosis seen on pre-implantation biopsy has not been well studied. We retrospectively evaluated 20 dual kidney transplant (DKT) and 28 single (SKT) kidney transplant recipients with >or=12 months follow-up from donors with moderate arteriosclerosis (>or=25% luminal diameter narrowing). Death censored graft survival was 100% and 79%, respectively (p = 0.0339). DKT recipients had significantly lower mean creatinine levels at one, three, six, and nine months and spent somewhat less time on the waiting list (181 +/- 160 vs. 318 +/- 306 d, p = 0.1429). DKT patients received kidneys from significantly older donors (64 +/- 7 vs. 54 +/- 11 yr; p = 0.0012), proportionately more expanded criteria donors (95% vs. 54%; p = 0.0029), and more donors with hypertension (81% vs. 48%, p = 0.0344) and death related to cerebrovascular accident (100% vs. 71%, p = 0.0143); however, more DKT kidneys underwent machine perfusion (95% vs. 57%, p = 0.0068). Baseline recipient variables were comparable between the two groups including age, race, gender, retransplantation, and HLA mismatch. Pre-implant biopsy was notable for similar frequencies of moderate interstitial fibrosis (10% vs. 14%, respectively) and glomerulosclerosis. Among recipients of deceased-donor kidneys with >25% arteriosclerosis, short-term outcomes after DKT were superior to that of SKT grafts. This approach may help to expand the donor-organ pool while optimizing outcomes.

Histopathological analysis of the reproductive system of male dogs experimentally infected with Toxoplasma gondii

The present research aimed to describe possible histopathological alterations in the reproductive system (testicles and epididymis) of male dogs experimentally infected with Toxoplasma gondii. Canines (n=10) serologically negative for T. gondii were selected and distributed into three experimental groups: GI, 3 inoculated with 2.0 x 10(5)P strain oocysts; GII, 3 infected with 1.0 x 10(6)RH strain tachyzoites; and GIII, 4 control dogs. Antibody research (IFAT) against T. gondii was realized. Toxoplasma gondii infection was confirmed by seroconversion of the 6 males infected with tachyzoites and oocysts from postinoculation day (PID) 7 and 14, respectively. At PID 70, all dogs were submitted to orchiectomy and testicle and epididymis samples were collected and histologically processed for examination under optical microscope. The following alterations were diagnosed: mild and moderate mononuclear inflammatory infiltrate in the epididymis, moderate cellular edema, hydropic degeneration and moderate interstitial fibrosis in seminiferous tubules. The histopathological results in the present research, isolation of T. gondii in testicle and epididymis fragments by immunohistochemistry and results from the literature by other authors in different tissues, all infer that the alterations observed in dogs infected with T. gondii are suggestive of toxoplasmic infection.

Are the current chronic allograft nephropathy grading systems sufficient to predict renal allograft survival?

A major problem in renal transplantation is identifying a grading system that can predict long-term graft survival. The present study determined the extent to which the two existing grading systems (Banff 97 and chronic allograft damage index, CADI) correlate with each other and with graft loss. A total of 161 transplant patient biopsies with chronic allograft nephropathy (CAN) were studied. The samples were coded and evaluated blindly by two pathologists using the two grading systems. Logistic regression analyses were used to evaluate the best predictor index for renal allograft loss. Patients with higher Banff 97 and CADI scores had higher rates of graft loss. Moreover, these measures also correlated with worse renal function and higher proteinuria levels at the time of CAN diagnosis. Logistic regression analyses showed that the use of angiotensin-converting enzyme inhibitor (ACEI), hepatitis C virus (HCV), tubular atrophy, and the use of mycophenolate mofetil (MMF) were associated with graft loss in the CADI, while the use of ACEI, HCV, moderate interstitial fibrosis and tubular atrophy and the use of MMF were associated in the Banff 97 index. Although Banff 97 and CADI analyze different parameters in different renal compartments, only some isolated parameters correlated with graft loss. This suggests that we need to review the CAN grading systems in order to devise a system that includes all parameters able to predict long-term graft survival, including chronic glomerulopathy, glomerular sclerosis, vascular changes, and severity of chronic interstitial fibrosis and tubular atrophy.

Renal ischaemic injuries during the use of zolmitriptan for treatment of migraines in a transplanted patient under tacrolimus therapy

A 26-year-old female patient underwent kidney transplantation from a 38-year-old deceased donor in 2001. Her renal disease was a focal segmental hyalinosis secondary to congenital vesico-ureteral reflux. She was started on triple immunosuppressive therapy [tacrolimus, mycophenolate mofetil (MPM) and prednisone]. Renal transplantation was complicated by delayed graft function and a renal biopsy was performed on the day 8, showing histological signs of tubular necrosis without acute rejection. Thereafter, evolution was excellent and corticosteroids were stopped after 1 year. Creatinine at 1 year was 100 mmol/l. She had arterial hypertension which was treated with four antihypertensive drugs just after renal transplantation; the treatment was progressively decreased and 18 months after transplantation, she required no further antihypertensive therapy. A routine renal biopsy was performed after steroid withdrawal in 2002, showing no evidence of rejection but a moderate interstitial fibrosis (10–20%). Tacrolimus and MPM were continued and trough levels of tacrolimus were aimed for 6–8 mg/l. All follow-up visits between 2002 and 2005 were unremarkable, except one respiratory infection which was treated with antibiotics for 7 days. Renal function was extremely stable with values averaging 100 mmol/l (83–114 mmol/l) of creatinine during these 3 years (Figure 1). She had no proteinuria (170mg/day). Tacrolimus trough level was kept between 6 and 8 mg/l with 1.5mg b.i.d. During this period, she was also taking an oral contraception (estradiol and progesterone), magnesium and paracetamol for common migraines. She did not smoke or drink alcohol. During the summer of 2005 her common migraines became exacerbated, no longer relieved by paracetamol. In September 2005, her general practitioner prescribed zolmitriptan 2.5mg to good effect. She used this medication 3–4 times a month. In October 2005 she had a slight increase of creatinine at 120 mmol/l, but no other changes which might have raised any concerns for her renal function; a control in January was stable at 115 mmol/l. Due to an increase in her headaches, she took zolmitriptan more frequently during the following 2 months, reporting an average consumption of 10 pills per week (Figure 1). She did not complain of abdominal pains. In March 2006, a control showed a creatinine value at 161 mmol/l associated with an increase in proteinuria (500mg/day) (Figure 1). There was no clinical explanation for this rise, but tacrolimus trough levels were at the upper limit of the target (8 mg/l) during the last 4 months under the same drug regimen (1.5mg b.i.d). A renal biopsy was performed. Several cortical ischaemic scars were observed with globally sclerotic glomeruli and arteriosclerosis (Figure 2A). The cortical region without scars included eight glomeruli, four of them globally sclerosed. Two glomeruli showed severe ischaemic injury with corrugation of the basement membranes (Figure 2B). In the two other glomeruli, lesions of focal and segmental sclerosis were observed. Some intratubular calcifications were detected. Arterioles appeared unremarkable. A 99m-Tc-DMSA renal scintigraphy was done, which did not reveal renal defects compatible with large scars. Zolmitriptan and tacrolimus were suspected to be involved in this acute decline in renal function. Zolmitriptan was stopped and tacrolimus dosage was slightly decreased, to 1mg in the morning and 0.5mg in the evening. Creatinine slowly decreased to 141 umol/l and a renal biopsy was performed again in June 2006. The histology showed the same cortical scars, and moderate arteriolar lesions Correspondence to: Pierre-Yves Martin, Service de Nephrologie, Departement de Medecine Interne, Hopitaux Universitaires de Geneve, 1211 Geneve 4, Switzerland. Email: pierre-yves.martin@hcuge.ch Nephrol Dial Transplant (2007) 22: 3341–3343

Infection in Renal Transplantation: A Case of Acute Q Fever

Acute Q fever is a zoonotic infection that most often occurs as an asymptomatic or very mild febrile illness. A small percentage of patients go on to develop chronic Q fever months or even years after the acute infection. We present a case of acute Q fever occurring in a renal transplant recipient who developed severe systemic disease with renal involvement. Serological diagnosis was carried out, and the patient was treated successfully with antibiotic therapy. This case emphasizes Q fever as one of the atypical infectious agents that may have serious consequences in immunocompromised renal transplant recipients and reminds us of the importance of careful inquiry regarding personal or occupational activities that could lead to exposure to specific organisms.

Therapeutic options in BK virus-associated interstitial nephritis

CASE PRESENTATION A female in her 30s developed renal failure secondary to mixed connective tissue disease-associated immune complex glomerulonephritis. Her past medical and family history was otherwise unremarkable. She underwent a pre-emptive renal transplantation from her mother, receiving induction with dacluzimab and had an uneventful post-transplant course. Her immunosuppressive regimen at discharge included prednisone 5 mg daily, mycophenolate mofetil 1000 mg twice daily, tacrolimus 4 mg twice daily, and prophylaxis with oral gancyclovir and trimethoprim–sulfamethoxazole, atenolol for hypertension, and famotidine, iron and calcium/vitamin D supplements. Her baseline serum creatinine after the transplant was 1.5 mg/dl. Two years after receiving the transplant, she developed fever and dysuria and was treated for a presumed urinary tract infection (negative urine cultures). Her serum creatinine during this episode increased to 1.9 mg/dl and remained elevated in this range. Her physical examination was unremarkable and her blood pressure was 130/80 mm Hg. A renal ultrasound did not show any abnormalities. A renal biopsy was performed. RENAL BIOPSY FINDINGS Sampling for light microscopy consisted of a single core of renal cortex containing eight glomeruli, all of which appeared histologically unremarkable. There was diffuse, moderate to severe interstitial inflammation involving the entire cortex sampled, and composed of lymphocytes and less prominent plasma cells. The interstitial inflammation extended across tubular basement membranes to produce extensive tubulitis with multiple tubules containing greater than 10 lymphocytes. Proximal tubules also displayed diffuse degenerative changes and interspersed, enlarged, hyperchromatic nuclei with intranuclear viral inclusions typical of BK virus. This diagnosis was subsequently confirmed by immunohistochemical staining for SV40. There was moderate tubular atrophy and interstitial fibrosis involving 50% of the cortex sampled. Blood vessels appear unremarkable (Figure 1). The renal biopsy findings were diagnostic of BK virusassociated interstitial nephritis (BKVIN). In the light of the diffuse distribution of the interstitial inflammation and tubulitis but more localized viral inclusions, the possibility of coexistent acute cellular rejection could not be excluded.

Histological analysis on adhesive molecules of renal intravascular large B cell lymphoma treated with CHOP chemotherapy and rituximab

A 48-year-old man was admitted to our hospital for investigation of mild renal dysfunction. A blood examination revealed mild elevation of creatinine level (1.77 mg/dl). Urinary examination revealed mild protein excretion (0.54 g/day) and microhematuria; renal biopsy revealed the focal proliferation of large mononuclear cells with mitosis in glomerular capillaries. According to immunohistochemical analysis, the intravascular lymphomatous cells stained positively with anti-leukocyte common antigen (LCA: CD45) and CD20, indicating a B lymphocyte lineage. In electron microscopy, the glomerular capillary was filled with lymphoma cells and epithelial foot process fusion was noted. Immunohistochemical analysis on adhesive molecules revealed a lack of CD11a expression on lymphoma cells, but positive CD54 expression on endothelial cells. Systemic 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) revealed no abnormal uptake of isotopes. On the basis of these findings, we diagnosed intravascular diffuse large B cell lymphoma localized in the kidney. Despite treatment with rituximab and CHOP (prednisolone, doxorubicin, vincristine, cyclophosphamide) for 3 cycles at 1-month intervals, the renal dysfunction did not change. In histopathological analysis of the second biopsy, lymphoma cells disappeared, but focal segmental glomerulosclerosis and moderate interstitial fibrosis were noted. Electron microscopic findings revealed severe subendothelial edema with mesangial interposition, indicating severe endothelial damage. Epithelial foot process fusion was improved. These pathological analyses let us conclude that a lack of CD11a could be a candidate factor for prevention of the extravasation of lymphoma cells from blood vessels in our patient. We also presumed that the intraglomerular endothelial damage occurred due to chemotherapy-associated cell injury.

Chronic allograft nephropathy in athymic nude rats after adoptive transfer of primed T lymphocytes

The impact of presensitized T lymphocytes on the development of chronic allograft nephropathy (CAN) was investigated in nude athymic LEW.RNU recipients of F344 renal allografts. The recipients (n = 8) were reconstituted with 5 x 10(7) T lymphocytes primed against donor skin grafts to induce graft rejection. LEW.RNU (n = 8) and euthymic LEW recipients (n = 6) which underwent no further intervention after transplantation served as control groups. Adoptive transfer of primed T cells induced CAN in LEW.RNU rats. Their kidney function decreased progressively. After 90 days a moderate glomerulopathy, tubular atrophy and interstitial fibrosis were observed, vascular changes were only mild or absent. Cellular infiltrates were predominated by CD4+ T cells and ED1+ macrophages. Deposition of tenascin and laminin was enhanced. Grafts of euthymic recipients displayed only mild signs of CAN according to the Banff criteria. These data implicate an important role for the cellular immune response in the development of CAN.

Recurrent nephrotic syndrome after living‐related renal transplantation resistant to plasma exchange: report of two cases

We encountered two patients of recurrent nephrotic syndrome (NS) after renal transplantation that was resistant to plasma exchange (PEX). Case 1 was a 34-year-old man with a living-related renal transplant for type-I membranoproliferative glomerulonephritis (MPGN) related end-stage renal disease (ESRD). He developed overt proteinuria 7 months post-transplant and presented with NS 5 months later. Biopsy of the transplant kidney revealed recurrent type I MPGN, but no features of acute rejection (AR) or chronic allograft nephropathy (CAN). He was treated with cyclophosphamide (CP), oral prednisolone (40 mg/d), an anti-platelet agent, heparin sulfate, and PEX, but the nephrotic state persisted and renal function was deteriorated. He recommenced hemodialysis 3 yr and 9 months after renal transplant. Case 2 was a 47-year-old male who underwent living-related renal transplant for ESRD due to focal segmental glomerulosclerosis (FSGS). He presented with proteinuria shortly after renal transplantation. He also had frequent episodes of AR. Graft biopsy revealed recurrent FSGS. Treatment of pulse methylprednisolone and PEX was transiently effective, but NS relapsed shortly after PEX. Graft biopsy at our hospital showed features of CAN with moderate interstitial fibrosis and tubular atrophy, presence of intraglomerular foam cells but no segmental sclerosis. Treatment with 12 courses of low-density lipoprotein apheresis (LDL-A) reduced proteinuria from 9.6 to 2.0 g/d, and incomplete remission has been maintained for more than 1 yr after LDL-A with slowly progressive renal dysfunction. Despite recent therapeutic advances, including the use of immunosuppressants and PEX, treatment of recurrent disease remains difficult. The LDL-A might be useful in cases with recurrent FSGS resistant to PEX.

Diltiazem Attenuates Oxidative Stress in Diabetic Rats

Diabetic nephropathy is the main cause of end stage renal damage. Oxidative stress is involved in the etiology of diabetic nephropathy and intracellular calcium is reported to play a considerable role in the development of renal damage in the diabetic kidney. Calcium antagonism can slow the progression of renal impairment in diabetes. The present study was thus designed to examine the effect of a nondihydropyridine calcium channel blocker, diltiazem, on renal function, oxidative stress, and nitric oxide (NO) release in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by a single intraperitoneal injection of STZ (65 mg/kg) in rats. After 4 weeks of STZ injection, the rats were divided in to four groups: control rats, diabetic rats treated with saline, and two groups of diabetic rats treated with diltiazem (5 and 10 mg/kg, i.p, respectively) for 8 weeks starting from 4 weeks after STZ injection. Renal function was assessed by creatinine, blood urea nitrogen, creatinine clearance, and urea clearance. Oxidative stress was measured by renal malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), and catalase. We also measured renal nitrite levels. At the end of the 8 weeks, diabetic rats exhibited renal dysfunction as evidenced by reduced creatinine and urea clearance along with enhanced albumin excretion rate as compared with control rats. Biochemical analysis of kidneys revealed a marked increase in oxidative stress demonstrated by increased lipid peroxidation and decreased activities of key antioxidant enzymes, GSH, SOD, and catalase in diabetic rats. Release of NO also significantly higher in diabetic rats than controls. Chronic treatment with diltiazem in diabetic rats significantly attenuated both renal dysfunction and oxidative stress along with increased NO levels as compared with untreated diabetic rats. The kidneys of diabetic rats showed morphological changes such as hyaline casts, glomerular thickening, and moderate interstitial fibrosis and arteriolopathy, whereas diltiazem administration markedly prevented diabetic-induced renal morphological alterations. The present study suggests that oxidative stress/nitrosative stress is increased in the diabetic kidney and calcium channel blockage can prevent these changes. The results also suggest that in STZ-induced diabetic rats, the protective action of diltiazem might be mediated, at least in part, by its effect on tissue oxidant/antioxidant status.

The effect of stone-wool on rat lungs and on the primary culture of rat alveolar macrophages and type II pneumocytes

The effect of stone-wool has been studied in both in vivo long term sequential and in vitro methods in male Sprague-Dawley rats. Stone-wool was administered by single intratracheal instillation and the lungs were examined after 1, 3 and 6 months of exposure by morphological methods. UICC crocidolite was applied as a positive control. In addition, the effects of both fibres were examined in primary cultures of alveolar macrophages (AM) and type II pneumocytes (T2) by morphological, biochemical and immunological methods. By the end of 6 months stone-wool induced moderate pulmonary interstitial inflammation and fibrosis without progression, whereas crocidolite induced progressive interstitial inflammation and fibrosis as a function of time. Although stone-wool inhibited phagocytosis, it did not induce serious membrane damage to the cells examined and did not destroy their ultrastructure. It significantly reduced the activity of Cu,Zn/superoxide dismutase (SOD) and alkaline phosphatase (AP) in alveolar macrophages and significantly decreased the activity of AP and gamma-glutamyl transpeptidase (GGT) in type II pneumocytes. Crocidolite, on the other hand, decreased the activity of all enzymes (glutathione peroxidase, GSH-Px; glutathione reductase, GSH-Rd) of glutathione metabolism as well as alkaline phosphatase in alveolar macrophages. It decreased the activity of all enzymes in type II pneumocytes, except for Cu,Zn/SOD. On exposure to stone-wool, the production of inflammatory proteins, macrophage chemoattractant protein-1 (MCP-1) and macrophage inhibitory protein-1alpha (MIP-1alpha) increased in both cultured cells but did not reach the level induced by crocidolite. Our results suggested that stone-wool is less toxic than crocidolite. Whether it is carcinogenic or not, is still an open question.

Histopathological evaluation of 0-h biopsy specimens of donor kidney procured by laparoscopic donor nephrectomy.

We evaluated the histopathology of donor kidneys procured by laparoscopic donor nephrectomy (LDN), by examining allograft biopsy specimens obtained immediately after donor nephrectomy (0-h biopsies). LDN was performed on 65 donors between December 1999 and November 2002, in our institution. Their mean age was 56 years, and there were 19 males and 46 females. Hand-assisted LDN (HALDN) was used in 10 cases and retroperitoneal LDN (RPLDN) in 55 cases. Allograft biopsy of all 65 kidneys was performed immediately after LDN (0-h biopsy), and the biopsy specimens were used in this study. All specimens were routinely examined by light and immunofluorescence microscopy. The 43 donors who underwent traditional open donor nephrectomy (ODN) between January 2001 and June 2001 served as controls. There was no significant difference in the rate of glomerular sclerosis and moderate interstitial fibrosis with tubular atrophy, the severity of arteriosclerosis, and the severity of arteriolar hyalinosis among the specimens from kidneys removed by the three different methods: HALDN, RPLDN, and ODN. Prominent and characteristic histopathological changes which are not usually seen in 0-h biopsy specimens of kidneys obtained by traditional ODN were 'subcapsular cortical damage (SCCD) with capsular lesions (CL)'. The SCCD with CL changes included a subcapsular degeneration and necrosis of tubular cells and a congestion of glomerular and peritubular capillaries (SCCD) associated with haemorrhage and fibrin deposits in the renal capsule (CL). In this study, such characteristic 'SCCD with CL' findings were observed in 35 specimens (54%). The damage was much milder in donor kidneys procured by RPLDN than by HALDN. SCCD with CL occurred in donor kidneys procured by LDN, which may be due to a compression of the renal parenchyma and veins. RPLDN may be better method for donor nephrectomy.

Effect of Irbesartan on the Antioxidant Defence System and Nitric Oxide Release in Diabetic Rat Kidney

Background/Aims: Increased oxidative stress is involved in the aetiology of diabetic nephropathy, and angiotensin II is reported to play a considerable role in the development of renal damage in diabetic kidney. Angiotensin antagonism can slow the progression of renal impairment in diabetes. The present study was thus designed to examine the effect of an angiotensin II type 1 (AT1) receptor antagonist, irbesartan on renal function, oxidative stress and nitric oxide (NO) release in streptozotocin (STZ)-induced diabetic rats. Methods: Diabetes was induced by a single intraperitoneal injection of streptozotocin (65 mg/kg) in rats. After 4 weeks of STZ injection, rats were divided into four groups: the control rats, diabetic rats and diabetic rats treated with irbesartan (25 and 50 mg/kg, orally) respectively till 8 weeks starting from 4 weeks after STZ injection. Renal function was assessed by creatinine, blood urea nitrogen, creatinine clearance and urea clearance. Oxidative stress was measured by renal malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase. We also measured renal nitrite levels. Results: At the end of the 8th week, diabetic rats exhibited renal dysfunction as evidenced by reduced creatinine and urea clearance along with enhanced albumin excretion rate as compared with control rats. Biochemical analysis of kidneys revealed a marked increase in oxidative stress demonstrated by increased lipid peroxidation and decreased activities of key antioxidant enzymes, GSH, SOD and catalase in diabetic rats. NO release was also significantly higher in diabetic rats than controls. Chronic treatment with irbesartan in diabetic rats significantly attenuated both renal dysfunction and oxidative stress along with increased NO levels as compared with untreated diabetic rats. The kidneys of diabetic rats showed morphological changes such as hyaline casts, glomerular thickening and moderate interstitial fibrosis and arteriolopathy, whereas irbesartan administration markedly prevented diabetic-induced renal morphological alterations. Conclusions: The present study suggests that oxidative stress/nitrosative stress is increased in the diabetic kidney and AT1 receptor blockade can prevent these changes. The results also suggest that in STZ-induced diabetic rats, the protective action of irbesartan might be mediated, at least in part, by its effect on tissue oxidant/antioxidant status.

Interspecies Differences in the Nephrotoxic Response to Cyclooxygenase Inhibition

In contrast to cyclooxygenase‐1 (COX‐1), the basal expression of renal cyclooxygenase‐2 (COX‐2) varies among species. High basal levels of COX‐2 in the renal cortex and papilla in dogs compared with monkeys suggest that COX‐2 inhibition may lead to distinct nephrotoxic responses. In this study, we compared the renal effects of COX inhibition between dogs and cynomolgus monkeys (n = 6/group) following the administration of naproxen sodium, a non‐selective COX‐1/COX‐2 inhibitor. Dogs and monkeys were treated with 50 or 150 mg/kg/day naproxen sodium, respectively, for 2 to 6 weeks. Naproxen doses used in this study resulted in equivalent inhibition of COX activity in both species as measured by reductions in urinary prostaglandin E2 (PGE2) and 6‐keto‐PGF1‐α levels. There was prominent reduction in renal blood flow (43%) and urinary sodium excretion (62%) in dogs but no alterations in renal blood flow and only minimal change (19%) in urinary sodium excretion in monkeys. The canine but not monkey kidney showed prominent COX‐2 expression in the macula densa, thick ascending limb of Henle and papillary interstitial cells by immunohistochemistry. After treatment, the canine but not monkey kidneys had mild to moderate renal tubular atrophy and interstitial fibrosis and renal papillary necrosis. Obstructive nephropathy secondary to intra‐tubular drug accumulation was seen in monkeys but not in dogs. Collectively, these data demonstrate species differences in the renal response to COX inhibition. The nature of functional and morphologic changes suggests a more prominent role of COX‐2 in renal hemodynamics and natriuresis in dogs than in monkeys.

Urinary amino-terminal propeptide of type III procollagen (PIIINP) as a marker of interstitial fibrosis in renal transplant recipients.

Interstitial fibrosis in the protocol biopsy specimens of transplanted kidneys is regarded as the most reliable predictor of future impaired renal function. Type I and III collagens are the main components of renal fibrosis. During the synthesis and deposition of type III collagen, an amino-terminal propeptide (PIIINP) of a molecular weight of 44 kDa is degraded from the collagen and secreted into surroundings. Increased circulating PIIINP has been shown to reflect ongoing fibrotic processes. The extent of interstitial fibrosis in 6-month protocol biopsy specimens was recorded, and the urinary excretion of PIIINP in 24-hr urine specimens was measured in 79 graft patients. We also measured the urinary excretion of transforming growth factor (TGF)-beta 1, alpha(1)-microglobulin (alpha(1)M), and albumin and recorded the changes in creatinine clearance during 0.5 to 6 (mean, 4.3) posttransplant follow-up years. The urinary excretion of PIIINP was significantly lower in patients with no interstitial fibrosis compared with patients with mild or moderate interstitial fibrosis (P<0.01). The urinary PIIINP-to-creatinine ratio correlated closely with the extent of interstitial fibrosis (r=0.410, P<0.001), with TGF-beta 1-to-creatinine (r=0.585, P<0.001) and alpha(1)M-to-creatinine (r=0.438, P<0.001) but not with the albumin-to-creatinine ratio. There was a close correlation between urinary TGF-beta 1 and alpha(1)M (r=0.508, P<0.001), whereas no correlation was found between urinary and serum PIIINP or between urinary PIIINP-to-creatinine ratio and glomerular filtration rate (GFR). During the follow-up, the GFR decreased in 42% of patients with a PIIINP-to-creatinine ratio over 100 ng/mmol, but only in 8% of patients with a ratio less than 100 ng/mmol (P<0.01). These findings show that the urinary PIIINP-to-creatinine ratio reflects the ongoing fibrotic processes in the kidney. Tubular epithelial cell injury may initiate the fibrotic processes, and elevated concentrations of urinary TGF-beta 1 and alpha(1)M may associate with the increased production and deposition of collagen type III in the graft. We conclude that measurements of urinary excretion of PIIINP can be used as an early noninvasive indicator of renal fibrosis after kidney transplantation.

Cases from the Osler Medical Service at Johns Hopkins University

Presenting featuresA healthy 44-year-old man presented to the Johns Hopkins Hospital after two episodes of nonpurulent hemoptysis, each consisting of approximately one-half cup of blood. The episodes were painless and were preceded by minimal coughing. The blood was bright red and without clots. He denied a recent history of upper respiratory tract infection, chest trauma, chest pain, or nasal/sinus disease. He had a chronic nonproductive “smoker’s cough.” He denied a recent history of fevers, chills, night sweats, hematuria, joint pains, epistaxis, or weight loss, and had no allergies. His past medical history was notable for neurogenic diabetes insipidus and diet-controlled diabetes mellitus. His only medication was intranasal desmopressin acetate. He smoked two packs of cigarettes daily for more than 20 years and rarely drank alcohol.On physical examination, he was afebrile, with normal heart rate and blood pressure. His oxygen saturation was 94% on room air, and his respiratory rate was 16 beats per minute. His lungs were clear to auscultation bilaterally, without evidence of crackles or wheezes. He had bilateral digital clubbing. His white blood cell count was 10,770/mm3, with a normal differential. His hematocrit was 46%, and his platelet count was normal. Blood chemistries and urinanalysis were normal. A posteroanterior and lateral chest radiograph obtained on admission demonstrated moderate diffuse interstitial fibrosis involving the upper and lower lung (Figure 1A and 1B ). What is the diagnosis?

Histopathology of resected myocardium and outcome of partial left ventriculectomy.

Since preoperative hemodynamics are not proven to be a predictor of effects of partial left ventriculectomy (PLV), myocardial histopathology may be better correlated with effects and outcome of PLV. Myocyte size (micron) in the excised myocardium was measured in 338 patients undergoing PLV. Endocardial fibrosis, interstitial fibrosis, and inflammatory cell infiltration were enumerated as none = 0, mild = 1, moderate = 2, and severe = 3. These histopathologic observations were correlated with patients' postoperative survival. Reduced survival was seen in patients with advanced (> or = moderate) interstitial fibrosis in all patients (n = 338, p = 0.064) and in the subgroup with nonischemic etiology (n = 229, p = 0.0039). Although correlation between endocardial and interstitial fibrosis was significant (r = 0.55, p < 0.01), endocardial fibrosis failed to correlate with postoperative survival. While Chagas' disease was associated with severe inflammation and poor survival, the presence of inflammatory cell infiltration had no effect on survival in all patients combined (p = 0.943). Although most patients (n = 266, 79%) had myocyte diameter over 30 micron, those with less hypertrophy (< 30 micron, n = 70, 21%) had a tendency toward increased survival (p = 0.067) regardless of underlying etiology. Interstitial fibrosis may be an important factor in stratification of patients for repair (PLV) or replacement (transplantation). PLV may be more beneficial in patients with less hypertrophy, before develqpment of interstitial fibrosis. Endomyocardial biopsy might not predict the extent or variation in degree of interstitial fibrosis, which may be better evaluated by other metabolic or perfusion studies that measure overall myocardial histopathology and viability.

Immunohistochemical analysis of renin activity in chronic cyclosporine nephropathy in childhood nephrotic syndrome.

Although the pivotal role of activation of the intrarenal renin-angiotensin system (RAS) has been demonstrated in the rat model of chronic cyclosporine (CyA) nephropathy, it is still unclear whether intrarenal RAS activation is responsible for chronic CyA nephropathy in humans. Therefore, the distribution of renin in formalin-fixed, paraffin-embedded renal biopsy specimens obtained from 26 children who had idiopathic nephrotic syndrome (NS) and who were treated with long-term moderate-dose CyA was examined with the use of immunohistochemistry with rabbit polyclonal anti-human renin antibody. Nineteen patients had steroid-dependent NS, and 7 had steroid-resistant NS. However, CyA treatment led all of the latter patients into complete remission. All of the patients underwent renal biopsies at the start and the end of CyA treatment. In the pre-CyA specimens, immunoreactivity to renin was detected mainly in those parts of arterioles within the anatomically well-defined juxtaglomerular apparatus. In the post-CyA specimens, it was also detected in those parts of the vessels upstream from the juxtaglomerular apparatus. Moreover, the ratio of the number of renin-positive cells to the number of glomeruli (histologic renin index) increased significantly with long-term CyA treatment (from 1.26+/-0.24 to 4.30+/-0.40, P<0.0001). Eleven of the post-CyA specimens showed mild or moderate CyA-associated arteriolopathy (CAA), whereas 15 showed no CAA. The histologic renin index was significantly higher in specimens with CAA than in those without CAA (5.16+/-0.59 versus 3.67+/-0.48, P = 0.031). Seven CAA-positive patients underwent repeat biopsies 6 to 12 mo after discontinuing the CyA. Their specimens showed an improvement in the CAA and significantly lower histologic renin index compared with the post-CyA (from 4.18+/-0.69 to 2.10+/-0.25, P = 0.018). Eleven of the post-CyA specimens showed mild to moderate interstitial fibrosis, and 15 showed no fibrosis. There was no significant difference in immunoreactivity to renin between the specimens with interstitial fibrosis and those without. However, patients with interstitial fibrosis had significantly longer periods of heavy proteinuria during CyA therapy, because of either steroid-resistant NS or frequent relapses of NS (83+/-18 versus 35+/-12 d, P = 0.030). These findings indicate that long-term CyA treatment for idiopathic NS in children may stimulate renin production in arterioles. They also suggest that CyA-stimulated intrarenal RAS activation is responsible for the development of CAA and that CyA-induced interstitial fibrosis is potentiated by long-term heavy proteinuria and is at least partly independent of CyA-stimulated intrarenal RAS activation.

Active immunization of combined β1-adrenoceptor and M 2-muscarinic receptor peptides induces cardiac hypertrophy in rabbits

Background: The high prevalence of patients with dilated cardiomyopathy (DCM) with anti- β 1-adrenoceptor and/or anti-M 2-Muscarinic receptor autoantibodies in their sera has been observed. However, the pathophysiological role of these autoantibodies in the development of cardiomyopathy is unknown. We previously reported an experimental model of early-stage DCM-like cardiomyopathy induced by immunizing rabbits for 1 year with synthetic peptides corresponding to the sequence of the second extracellular loop of either β 1-adrenoceptor or M 2-Muscarinic receptor. Because approximately half the sera of patients with DCM that recognize one of the two receptor sequences also recognize the second sequence, a model was created in rabbits simultaneously immunized with the synthetic peptides corresponding to the second extracellular loop of the β 1-adrenoceptor and M 2-Muscarinic receptor. Methods and Results: All rabbits (n = 8) immunized with both peptides had a high titer of both anti- β 1-adrenoceptor and anti-M 2-Muscarinic receptor autoantibodies in their sera, whereas none of the sera from control rabbits injected with saline (n = 9) was positive. No significant cross-reaction with peptides other than those used for immunization was found. The weight of the hearts of immunized rabbits increased significantly. The hearts of immunized rabbits showed marked concentric left ventricular hypertrophy with mild inflammatory cell infiltration. In these rabbits, mild or moderate interstitial fibrosis was also observed. In electron micrographs, immunized rabbits showed focal myofibrillar lysis, loss of myofilament, and a marked increase in the number of mitochondria and deposition of dense granules in both sarcoplasm and myofibrils. Conversely, one of the control rabbits showed scant mononuclear cell infiltration. However, in this control rabbit, no significant alteration was found by electron microscopy. Conclusion: Our results showed the coexistence of both anti- β 1-adrenoceptor and anti-M 2-muscarinic receptor autoantibodies in the sera has pathophysiological importance, shown by their ability to induce cardiac hypertrophy in rabbits.